CN108594556A

CN108594556A - Display device

Info

Publication number: CN108594556A
Application number: CN201810385416.8A
Authority: CN
Inventors: 徐宏辉; 周修和
Original assignee: BOE Technology Group Co Ltd; BOE Optical Science and Technology Co Ltd
Current assignee: BOE Technology Group Co Ltd; BOE Optical Science and Technology Co Ltd
Priority date: 2018-04-26
Filing date: 2018-04-26
Publication date: 2018-09-28
Also published as: WO2019205976A1; US20200251065A1; US11315510B2

Abstract

The present invention provides a kind of display device, belongs to technical field of liquid crystal display, can at least partly solve the problems, such as that existing liquid crystal display device power consumption is high.The present invention display device include：Display panel with multiple sub-pixels comprising the multistable state liquid srystal to the first substrate and second substrate of box, and between first substrate and second substrate；Wherein, in each sub-pixel be equipped in multistable state liquid srystal formed electric field first electrode and second electrode, multistable state liquid srystal under not same electric field have different optical properties, and can electric field disappearance after keep electric field in the presence of state；Driving unit, for providing driving voltage to first electrode and second electrode to form electric field；Control unit, decide whether to send out control instruction to driving unit for whether being changed according to the display content of sub-pixel, control instruction is used to control driving unit and stops providing driving voltage to the first electrode and second electrode at least partly showing the unconverted sub-pixel of content.

Description

Display device

Technical Field

The invention belongs to the technical field of display, and particularly relates to a display device.

Background

In a conventional liquid crystal display device, a driving voltage is applied to driving electrodes (e.g., a pixel electrode and a common electrode) in each sub-pixel to generate an electric field, which can deflect liquid crystal in a desired manner, thereby generating different degrees of filtering in each sub-pixel to realize display.

In the conventional liquid crystal display device, it is necessary to maintain an electric field to maintain a desired deflection state of liquid crystal, and therefore, in order to realize display, a driving voltage must be constantly supplied to a driving electrode, resulting in high driving power consumption.

Disclosure of Invention

The invention at least partially solves the problem of high power consumption of the existing liquid crystal display device and provides a display device with low power consumption.

The technical scheme adopted for solving the technical problem of the invention is a display device, which comprises:

the display panel with a plurality of sub-pixels comprises a first substrate and a second substrate which are opposite to each other, and multi-stable liquid crystal arranged between the first substrate and the second substrate; the liquid crystal display comprises a plurality of sub-pixels, wherein each sub-pixel is provided with a first electrode and a second electrode which are used for forming an electric field in multistable liquid crystal, and the multistable liquid crystal has different optical properties under different electric fields and can keep the optical properties when the electric field exists after the electric field disappears;

a driving unit for supplying a driving voltage to the first and second electrodes to form an electric field;

and the control unit is used for determining whether to send a control instruction to the driving unit according to whether the display content of the sub-pixel is changed, and the control instruction is used for controlling the driving unit to stop supplying the driving voltage to the first electrode and the second electrode of the sub-pixel of which at least part of the display content is not changed.

Preferably, the control unit is configured to issue a control instruction to the driving unit only when the display content of all the sub-pixels has no change, and the control instruction is used for controlling the driving unit to stop operating.

More preferably, the first electrode is provided on a side of the first substrate facing the second substrate;

the second electrode is arranged on one side of the second substrate facing the first substrate, and the first electrode and the second electrode in the same sub-pixel are oppositely arranged;

wherein,

the first electrodes in the sub-pixels are connected into a whole to form a common electrode; or the second electrodes in the sub-pixels are connected to form a common electrode.

Preferably, the multistable liquid crystals have different transmittances under different electric fields.

Preferably, the display panel is a reflective display panel having a light incident side, and a reflective layer is disposed at a position farther from the light incident side than the multistable liquid crystal.

It is further preferable that the first substrate is closer to the light incident side than the second substrate;

the first electrode is arranged on one side of the first substrate facing the second substrate;

the light reflecting layer is arranged between the second substrate and the second electrode.

Further preferably, the sub-pixels are divided into different colors, color filter films corresponding to the colors of the sub-pixels are arranged in the sub-pixels, and the color filter films are closer to the light incident side than the reflective layer;

wherein,

the color filter film is arranged on one side of the first substrate, which faces the second substrate; or the color filter film is arranged on one side of the second substrate facing the first substrate.

Preferably, the first electrode is disposed on a side of the first substrate facing the second substrate;

the second electrode is arranged on one side of the second substrate facing the first substrate and is opposite to the first electrode.

Preferably, the sub-pixels are divided into different colors, and color filter films corresponding to the colors of the sub-pixels are arranged in the sub-pixels.

Preferably, the display device is any one of an electronic calendar, an electronic watch, an electronic gas meter, an electronic electricity meter, and an electronic water meter.

Drawings

FIG. 1 is a schematic partial cross-sectional view of a display device in one state according to an embodiment of the present invention;

FIG. 2 is a schematic partial cross-sectional view of a display device in another state according to an embodiment of the present invention;

FIG. 3 is a schematic partial cross-sectional view of another display device according to an embodiment of the invention;

FIG. 4 is a diagram illustrating a correspondence between a sub-pixel luminance and an electric field in a display device according to an embodiment of the present invention;

wherein the reference numerals are: 11. a first electrode; 12. a second electrode; 2. multistable liquid crystal; 3. a light-reflecting layer; 5. a sub-pixel; 91. a first substrate; 92. a second substrate.

Detailed Description

In order to make the technical solutions of the present invention better understood, the present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

Example 1:

as shown in fig. 1 to 4, the present embodiment provides a display device, which includes:

a display panel having a plurality of sub-pixels 5, which includes a first substrate 91 and a second substrate 92 facing each other, and a multi-stable liquid crystal 2 disposed between the first substrate 91 and the second substrate 92; wherein, each sub-pixel 5 is provided with a first electrode 11 and a second electrode 12 for forming an electric field in the multistable liquid crystal 2, and the multistable liquid crystal 2 has different optical properties under different electric fields and can keep the optical properties when the electric field exists after the electric field disappears;

a driving unit for supplying a driving voltage to the first electrode 11 and the second electrode 12 to form an electric field;

and the control unit is used for determining whether to send a control instruction to the driving unit according to whether the display content of the sub-pixel 5 is changed, and the control instruction is used for controlling the driving unit to stop supplying the driving voltage to the first electrode 11 and the second electrode 12 of the sub-pixel 5 of which at least part of the display content is unchanged.

The above display device has a display panel including two opposing substrates, a multi-stable liquid crystal 2 filled between the two substrates, and two electrodes provided in each sub-pixel 5, the two electrodes being capable of forming an electric field in the multi-stable liquid crystal 2 at the sub-pixel 5, thereby changing the state and optical properties of the multi-stable liquid crystal 2, and further causing the sub-pixel 5 to display desired content. Among them, the multistable liquid crystal 2 is a known liquid crystal material, which has different states under different electric fields and can produce different optical properties (such as transmittance, change of polarization direction of light, etc.); when the electric field is removed, the multistable liquid crystal 2 remains in the state where the previous electric field was present, i.e. retains the previous optical properties.

The display device also comprises a control unit for detecting whether the display content of the sub-pixels 5 in the display panel changes (i.e. whether at least part of the display positions display a static picture), and determining whether to send a control instruction according to the change, and if the control instruction is sent, the control unit can control the drive unit to stop supplying the drive voltage to the sub-pixels 5 (at least part of the display positions) displaying the static picture, so that the output of the drive unit is reduced, and the drive power consumption is reduced.

In the sub-pixel 5 which stops receiving the driving voltage, no voltage is present on the first electrode 11 and the second electrode 12, so the electric field between the two electrodes also disappears, but because the multi-stable liquid crystal 2 is used in the display panel, the state and the optical property of the multi-stable liquid crystal 2 at the sub-pixel 5 are not changed, therefore, the sub-pixel 5 still keeps displaying the previous content (i.e. the content obtained after the last change), and the display effect is not affected.

In the display device of the embodiment, the control unit controls the driving unit to stop providing the driving voltage to the corresponding sub-pixel 5 (or make the driving unit sleep as a whole) when the display content is unchanged, thereby reducing the output of the driving unit and reducing the driving power consumption; meanwhile, because the multistable liquid crystal 2 is adopted, the sub-pixel 5 can keep the content displayed before in the absence of an electric field, and the display effect is not influenced by the above mode.

The control unit knows whether the display content of the sub-pixel 5 changes in various ways, for example, it can analyze the display data (i.e. the data describing what picture should be displayed) of each frame from the display card, and determine whether the picture of the adjacent frame has the same position pattern; alternatively, the display card may provide new display data only when the display contents are changed, so the control unit may determine whether the display contents are changed by whether the new display data are received.

The multistable liquid crystal 2 can have two different states under only two different electric fields and has two corresponding optical properties (such as light transmission and light non-transmission), so that the sub-pixel 5 can only realize black and white display. Alternatively, the multi-stable liquid crystal 2 may have a plurality of different states under a plurality of different electric fields and have a plurality of corresponding optical properties (e.g., different degrees of light transmittance), so that the sub-pixel 5 can display a plurality of different gray scales (e.g., 16 gray scales).

The actual relationship curve of luminance versus electric field (electric field strength) of the sub-pixel 5 can be shown in fig. 4, when the electric field strength is increased from 0 to M, the luminance is also increased from a to B, and when the electric field strength is decreased to 0 (i.e. when the driving voltage is no longer supplied), the luminance is slightly decreased to C. However, since the difference between the brightness of B and C is small and within the unavoidable error range, it is still considered that the state and optical properties of the multistable liquid crystal 2 are not changed after the electric field is removed.

The control unit and the driving unit may be independent integrated circuits, chips, processors, etc., or may be integrated in one integrated circuit, chip, processor, etc.

The driving unit may provide a driving voltage to the electrodes in each sub-pixel 5 through a single lead (only schematically shown in the figure as being connected to the second electrode 12 of one sub-pixel 5), or may provide a driving voltage to the electrodes in each sub-pixel 5 in a scanning manner through a "gate line + data line" structure.

Preferably, the first electrode 11 is provided on the side of the first substrate 91 facing the second substrate 92; the second electrode 12 is provided on the second substrate 92 facing the first substrate 91 and is opposed to the first electrode 11.

That is, the two electrodes may be respectively provided inside the two substrates and opposed to each other, thereby forming an electric field in the multistable liquid crystal 2 most effectively.

Preferably, the sub-pixels 5 are divided into different colors, and color filters corresponding to the colors of the sub-pixels 5 are disposed therein.

That is, each sub-pixel 5 of the display panel may be provided with a color filter (e.g., a red filter R, a green filter G, and a blue filter B) of a corresponding color, so as to filter the light emitted from each sub-pixel 5 into a corresponding color, thereby implementing a color display. If the sub-pixels 5 can also display different gray scales, the final display device can display full color.

The sub-pixels 5 (e.g. red sub-pixel, green-red sub-pixel, and blue sub-pixel) of different colors can be combined into a pixel, and the pixel is used as a minimum visible point in the display panel.

Preferably, the control unit is configured to issue a control instruction to the driving unit only when the display content of all the sub-pixels 5 has no change, and the control instruction is used to control the driving unit to stop operating.

That is, the control unit preferably issues a control instruction only when the display content of the entire display panel is a static screen, so as to control the entire driving unit to stop working (i.e., to sleep); if only a part of the display screen in the display panel is static (i.e. only a part of the sub-pixels 5 have no change in display content), no control command is issued, so that the driving unit still provides the driving voltage to both the sub-pixels 5 with the changed display content and the unchanged display content.

For the driving unit, even if the driving voltage is only provided to part of the sub-pixels, the sub-pixels are still in the working state and still have high power consumption, and when the sub-pixels stop working and enter the dormant state, almost no power consumption exists, and the energy-saving effect is most obvious. Therefore, the above method can not only obviously reduce the driving power consumption, but also reduce the difficulty of control.

It should be understood, of course, that after the driving unit stops working as a whole, if the display content of at least some of the sub-pixels 5 changes, the control unit should control the driving unit to start working again (i.e. wake up). Therefore, at this time, the driving unit is actually in the "board sleep" state, and can resume operation at any time, instead of the "fully off" state when the display device is completely turned off.

It should be understood that it is also possible, of course, if the control unit issues a control instruction to control the driving unit to stop supplying the driving voltage to the sub-pixels 5 whose display contents are not changed as long as the display contents of some of the sub-pixels 5 are not changed (at this time, if the display contents of all the sub-pixels 5 are not changed, the driving unit also stops supplying the driving voltage to all the sub-pixels 5). This way, the driving power consumption can be reduced to the maximum extent.

More preferably, the first electrode 11 is provided on the side of the first substrate 91 facing the second substrate 92; the second electrode 12 is disposed on the second substrate 92 facing the first substrate 91, and the first electrode 11 and the second electrode 12 in the same sub-pixel 5 are disposed oppositely; the first electrodes 11 of the sub-pixels 5 are connected to form a common electrode, or the second electrodes 12 of the sub-pixels 5 are connected to form a common electrode.

As shown in fig. 1 to 3, in the display device that provides the control command only when the display content is completely unchanged, if the first electrode 11 and the second electrode 12 are in the above opposite form, one of the electrodes (taking the first electrode 11 as an example) may be a common electrode, that is, the first electrodes 11 in the plurality of sub-pixels 5 may be connected together and loaded with the same driving voltage, so that the manufacturing process thereof may be simplified, and the circuit structure for supplying the first electrodes 11 with power may be simple.

Preferably, the display panel is a reflective display panel having a light incident side and a reflective layer 3 provided at a position farther from the light incident side than the multistable liquid crystal 2.

That is, the display panel is preferably of a reflective type, in which light enters from the light entrance side of the display panel, passes through the multistable liquid crystal 2, is reflected by the reflective layer 3, and then passes through the multistable liquid crystal 2 again and exits, thereby realizing display. The reflective display panel has an advantage in that it does not use a backlight source to provide light, and thus there is no power consumption of the backlight source therein, which can further reduce power consumption.

More preferably, the first substrate 91 is closer to the light incident side than the second substrate 92; the first electrode 11 is provided on the first substrate 91 on the side facing the second substrate 92; the second electrode 12 is disposed on the second substrate 92 facing the first substrate 91, and the first electrode 11 and the second electrode 12 in the same sub-pixel 5 are disposed oppositely; the light reflecting layer 3 is disposed between the second substrate 92 and the second electrode 12.

That is, for the above display device using the reflective display panel and the counter electrode, the light reflecting layer 3 is preferably provided on the substrate (second substrate 92) away from the light incident side and further away from the multistable liquid crystal 2 than the second electrode 12 so as to avoid an influence on the electric field.

It should be understood, of course, that if the light-reflecting layer 3 is made of a conductive material such as metal, at least one insulating layer 8 is provided between the light-reflecting layer and the second electrodes 12 so as not to conduct the second electrodes 12.

It will of course be appreciated that if the second electrode 12 itself is formed of a light reflecting material, the second electrode 12 may also serve as the light reflecting layer 3, i.e. there may be no separate light reflecting layer in the display panel.

Of course, as shown in fig. 1 to 3, the first electrode 11 on the first substrate 91 is described as a common electrode, and thus the common electrode is closer to the light incident side than the pixel electrode. It will be appreciated that it is also possible if the second electrode 12 takes the form of a common electrode, such that the common electrode is further from the light-entry side than the pixel electrode.

More preferably, the sub-pixels 5 are divided into different colors, and color filter films corresponding to the colors of the sub-pixels 5 are arranged in the sub-pixels 5, and the color filter films are closer to the light incident side than the light reflecting layer 3; the color filter is disposed on a side of the first substrate 91 facing the second substrate 92; alternatively, the color filter is disposed on the second substrate 92 facing the first substrate 91.

That is, the display device using the reflective display panel and the counter electrode may be provided with a color filter to realize color display; obviously, the color filter must be farther away from the light incident side than the reflective layer 3 to ensure that the reflected light can pass through the color filter.

Specifically, the color filter may be disposed on the side of the first electrode 11 facing the second substrate 92 as shown in fig. 1 and 2, or may be disposed on the side of the second electrode 12 facing the first substrate 91 as shown in fig. 3. Of course, it is also possible to use the color filter between the substrate and the electrode or on the side of the first substrate near the light incident side.

Preferably, the multistable liquid crystals 2 have different transmittances under different electric fields.

That is, the multistable liquid crystal 2 may have different degrees of transparency under different electric fields, thereby causing the sub-pixels 5 to have different brightness. For example, as shown in fig. 1, under a certain electric field, the molecules of the multistable liquid crystal 2 are regularly arranged, so that the multistable liquid crystal 2 is basically transparent as a whole, light is allowed to pass through (including reflection), and the brightness of the sub-pixel 5 is maximum; as shown in fig. 2, under another electric field, the molecular arrangement of the multi-stable liquid crystal 2 is irregular, and the incident light can be scattered randomly, and the light is absorbed after being reflected by a large amount inside the multi-stable liquid crystal and cannot be emitted, so that the multi-stable liquid crystal 2 is opaque as a whole, and the brightness of the sub-pixel 5 is minimum.

Of course, it should be understood that the above multistable liquid crystal 2 having different transmittances is not limited to use in the above reflective display panel, and it may be used in a transmissive display panel as well.

The multistable liquid crystal 2 has the advantages that the light emitted from the sub-pixel 5 does not need to be filtered by the polaroid, so that the inevitable brightness loss does not exist, the utilization rate of the light can be improved, and the structure of the display panel can be simplified (namely, the polaroid does not need to be arranged in the display panel).

As described above, the display device of the present embodiment mainly obtains the energy saving effect when the display content is not changed; compared with a computer display and the like, the display contents of the above devices are relatively less changed (for example, the display contents of the electronic calendar may be changed once a day), so that the present embodiment is particularly suitable for being adopted.

It will be understood that the above embodiments are merely exemplary embodiments taken to illustrate the principles of the present invention, which is not limited thereto. It will be apparent to those skilled in the art that various modifications and improvements can be made without departing from the spirit and substance of the invention, and these modifications and improvements are also considered to be within the scope of the invention.

Claims

1. A display device, comprising:

2. The display device according to claim 1,

the control unit is used for sending a control instruction to the driving unit only when the display contents of all the sub-pixels are unchanged, and the control instruction is used for controlling the driving unit to stop working.

3. The display device according to claim 2,

wherein,

4. The display device according to claim 1,

the multistable liquid crystal has different transmittance under different electric fields.

5. The display device according to claim 1,

the display panel is a reflective display panel, which has a light incident side, and a reflective layer is arranged at a position farther from the light incident side than the multistable liquid crystal.

6. The display device according to claim 5,

the first substrate is closer to the light incident side than the second substrate;

7. The display device according to claim 5,

the sub-pixels are divided into different colors, color filter films corresponding to the colors of the sub-pixels are arranged in the sub-pixels, and the color filter films are closer to the light incident side than the light reflecting layer;

wherein,

8. The display device according to claim 1,

9. The display device according to claim 1,

the sub-pixels are divided into different colors, and color filter films corresponding to the colors of the sub-pixels are arranged in the sub-pixels.

10. The display device according to claim 1,

the display device is any one of an electronic calendar, an electronic watch, an electronic gas meter, an electronic electric meter and an electronic water meter.